Rapid untargeted screening and determination of unknown contaminants in aquatic products by high performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry

Siyan Guo,Xiaojun Deng,Gongjun Yang,Weijian Shen,Han Liu,Hong Lin,Yao Yin,Xiaoyan Zhang,Bin Wu,Xionghai Yi,Tao Ding

doi:10.3724/sp.j.1123.2018.08043

Abstract

A method has been developed for rapid untargeted screening and determination of unknown contaminants in aquatic products by high performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry. The samples were extracted by acetonitrile, dried under nitrogen, dissolved in methanol-water (3:7, v/v), and analyzed via the full MS scan/data dependent MS2 mode during the screening process. The Trace Finder software was used to match the precise mass, the isotope abundance ratio, the fragment ion to search for unknown contaminants in aquatic samples. The optimized QuEChERS method is used to purify the samples when quantifying. The quantitative analyses of triazole, caffeine, and ethoxyquinoline were performed via the target-MS2 mode. The correlation coefficients of the three compounds in fish and shrimp samples were higher than 0.99 in the linear range of 5-1000 μg/L. The limit of detection was 1 μg/kg, and the limit of quantitation was 5 μg/kg. The average recoveries were between 70.5% and 90.9% with the relative standard deviations ranging from 5.4% to 12.8%. The screening method has the advantages of fast, accurate, and high throughput; when combined with the quantitative method, it can be used to screen and determine unknown contaminants in the actual aquatic products.

Highlights

The average recoveries were between 70􀆰 5% and 90􀆰 9% with the relative standard deviations ran⁃ ging from 5􀆰 4% to 12􀆰 8%
染物。采用优化后的条件对阳性样品进行三环唑、咖啡因、乙氧基喹啉的定量分析,结果表明,样品中三环唑的检出率为 1􀆰 2%,含量范围在 10􀆰 1 ~ 16􀆰 5 μg / kg; 咖啡因检出率为 1􀆰 7%,含量范围在 5􀆰 2 ~ 5􀆰 8 μg / kg; 乙氧基喹啉检出率为 1􀆰 2%,含量范围在 8􀆰 4 ~ 12􀆰 1 μg / kg。对结果进行分析,其中三环唑为农药污染物,推测是由于不规范使用农药带来的水源或农作物污染,进而富集到水产品中[19] ;咖啡因是一种优势污染物,在国内湖泊及地表水中均有检出,其常在咖啡、茶、巧克力及可乐型饮料中用作兴奋剂、苦味剂和香料;此外咖啡因也是一种重要的解热镇痛药,复方阿司匹林的主要成分之一, 在当今社会使用非常广泛[20,21] ,因此水产品检出咖啡因可能是由于水体污染造成的;乙氧基喹啉作为抗氧化剂常在饲料或渔用药物中投入使用。目前 GB 2763⁃2016 中制定了三环唑在稻谷和蔬菜中的最大残留限量为 2 mg / kg,水果中乙氧基喹啉的最大残留限量为 3 mg / kg[20] ,水产品中均无相关要求。水产品中农药限量仅滴滴涕和六六六两项[22] ,与发达国家相比处于被动和落后的局面,引起关注度较低,建议今后加强重视程度,继续开展深入的风险监测工作。

Summary

Introduction

The average recoveries were between 70􀆰 5% and 90􀆰 9% with the relative standard deviations ran⁃ ging from 5􀆰 4% to 12􀆰 8% . The screening method has the advantages of fast, accurate, and high throughput; when combined with the quantitative method, it can be used to screen and deter⁃ mine unknown contaminants in the actual aquatic products.

Results

Conclusion